1. Field of the Invention
This invention relates to an optical spectrum analyzer for analyzing an optical spectrum. This invention particularly relates to an optical spectrum analyzer for analyzing an optical spectrum by the utilization of acousto-optic effects.
2. Description of the Prior Art
Various optical spectrum analyzers for analyzing an optical spectrum have heretofore been known. As one of the optical spectrum analyzers which have widely been used in practice, for example, a Czerny-Turner type optical spectrum analyzer is known. The Czerny-Turner type optical spectrum analyzer is constituted to rotate a diffraction grating for diffracting light which is to be analyzed and which is irradiated to the diffraction grating, the diffracted light is thereby moved on a slit, and the optical spectrum is analyzed on the basis of the angle of rotation of the diffraction grating at the time of detection of the diffracted light across the slit. The optical spectrum analyzer of this type can analyze the optical spectrum at a high resolution.
However, the optical spectrum analyzer of the aforesaid type is large and heavy. Therefore, it cannot be easily processed and is not suitable as, for example, a portable device. Though various optical spectrum analyzers capable of being formed small and light have heretofore been proposed, many of them have the drawback that the resolution is low.